Cerebellar Infarction in a 9 Year Old Child Presenting with Fever and Ataxia: A Case Report

Cerebellar acute ischemic stroke (AIS) can be a complication of minor head trauma, vertebral artery dissection, vasospasm or systemic hypoperfusion. CT scan usually is negative few hours after acute infarction. Magnetic resonance imaging (MRI) is superior to CT scan for posterior fossa lesions and also in acute phase of cerebellar stroke especially in children. Here we report a 9 yr old girl referred to the Pediatric Emergency Room, Moosavi Hospital, Zanjan, Iran in January 2017 presenting with sudden onset of headache and recurrent vomiting, ataxia, and history of 3 consecutive days of fever and malaise. In the report of MRI, there were abnormal low T1 and high T2 signal intensity in left cerebellar hemisphere involving superior and middle cerebellar peduncles. After 4 days of admission, the patient became drowsy, symptoms progressed and transferred to the pediatric intensive care unit (PICU). The patient underwent hemispherectomy surgery of the left cerebellar hemisphere because of acute obstructive hydrocephaly. After 5 months of occupational therapy, the force of her extremities was normal and the ataxia completely disappeared. Childhood acute ischemic stroke although rare can happen with cerebellar involvement. Because in our patient the first brain CT scan was nearly normal and a false negative rate for initial computed tomography (CT) scanning of 60%-80% also contributes to missed and delayed diagnosis of childhood AIS, for every child presenting with acute ataxia without identified cause in addition to CT scan, MRI also being ordered and from the beginning besides other causes, stroke be contemplated as a cause of ataxia.


Introduction
Childhood Acute stroke (AIS) is a devastating event that can happen with cerebellar involvement occurring in a smaller subset of this group of patients (1). Documented examples of both hemorrhagic and non-hemorrhagic cerebellar stroke in children are available with listed outcomes ranging from occasional death, permanent neurological dysfunction and complete recovery (2). Ataxia, although rare, can be the most prevalent symptom for these children, so early diagnosis is critical.
Patients should be separated into two group, the patients with deteriorating condition and the patients with stable or improving condition and the treatment should be selected based on the patient condition (3). Overall scheme of therapeutic approach is to use supportive therapy and anticoagulant therapy. However, the most definite therapy is to reduce ICP with or without surgery according to the patient's condition (4).
Here we report a 9 yr old girl presenting with sudden onset of headache and recurrent vomiting, ataxia, and history of 3 consecutive days of fever and malaise. An informed consent was obtained from her parents in order to publish data as a case report without publishing her name. Ethics Committee of the university approved the study.

Diagnostic focus and assessment
The patient underwent a brain CT scan without contrast in first day of admission preceded by CBC, diff, BUN, Cr, Na, K, Arterial blood gas sampling (ABG) and Urine analysis. On the second day, brain magnetic resonance venography (MRV) and magnetic resonance imaging (MRI) with flair, T1, T2 and DWI sequences and also EEG were ordered, then lumbar puncture with 3 samples was carried out. About 48 h after the MRI the patient became aggressive and had severe headache, nausea and vomiting plus ataxia and delirium, then the patient transferred to PICU and we decided to order the second CT scan and after the results, we asked for urgent neurosurgery consultation and the patient was prepared for brain surgery. The day after surgery the patient underwent brain CT scan without contrast again and laboratory tests were repeated. The patient underwent the last brain CT scan without contrast on thirteenth day and also had an EEG on the same day. We also did a portable echocardiography plus electrocardiography to determine presence of any PFO or ASD or any cardiac problems.

Therapeutic focus and assessment
The patient presented with sudden onset of headache and recurrent vomiting, ataxia, and history of 3 consecutive days of fever and malaise.

Follow-up and outcomes
The first EEG report was mildly abnormal due to some spike and wave discharges (

Cerebellar Infarction in a 9 Year Old Child Presenting with Fever and Ataxia: A Case Report
HPLC Amino Acid profile was normal except lower than normal range of arginine (26.8) and higher than normal range of alanine (148.0).
We also obtained an Arterial Blood Gas sample from the patient that was normal ( Table 1) (2). "Underlying causes of the ischemic infarct cannot be explained in nearly half of cases" (5).
Ataxia, although rare, can be the most prevalent symptom for these children, so early diagnosis is critical. CT scan is the most commonly used modality for stroke and is widely available and accurately eliminates acute hemorrhage. In the first hours after acute infarction, CT scan is usually negative (6). MRI is superior to CT scan for posterior fossa lesions and also in acute phase of cerebellar ischemic stroke especially in children.
MRI with DWI sequences is more sensitive than conventional MRI.
Because in our patient the first brain CT scan was nearly normal and a false negative rate for initial computed tomography (CT) scanning of 60%-80% also contributes to missed and delayed diagnosis of childhood AIS, we conclude that for every child presenting with acute ataxia without identified cause in addition to CT scan, MRI also being ordered and from the beginning besides other causes, stroke be contemplated as a cause of ataxia.
In conclusion, MRI without any ionizing radiations as the superior modality for showing posterior fossa lesions should be ordered, in addition to CT scan, for every child presenting with ataxia without identified cause, and from the beginning besides other causes, stroke should be contemplated as a cause of ataxia.